How to handle String data in flutter_bluetooth_serial package?

Question

I'm using flutter_bluetooth_serial package to communicate with HC-05 bluetooth module in my Flutter app. The module is responsible to send the String HC05-1 Mode1 Data: 1.696728 V to my app in each second, however while receiving the data, the value was separated into several chunks like the following:

I/flutter (24772): Data incoming: H
I/flutter (24772): Data incoming: C05-1 Mo
I/flutter (24772): Data incoming: de1 Data:
I/flutter (24772): Data incoming: 1.696728
I/flutter (24772): Data incoming: V

Here is the Flutter code to receive data:

conn.input.listen((Uint8List data) {
          String dataStr = ascii.decode(data);
          print('Data incoming: $dataStr');
        })

Here is the C code I've got to send data:

sprintf((char*)sendbuf, "HC05-1 Mode1 Data: %f V\r\n", ttemp)
// send to bluetooth module
u2_printf("HC05-1 Mode1 Data: %f V\r\n", ttemp)

I there any way to receive the whole string value instead of the chunk at one time?

score 1 · Answer 1 · answered Mar 14 '21 at 12:25

Create variable  String message='';

then make changes in your function

conn.input.listen((Uint8List data) {
      String dataStr = ascii.decode(data);
      message+=dataStr;
        if (dataStr.contains('\n')) {
          print(message); // here you get complete string 
          message = '';   //clear buffer to accept new string
        }
    })

How to handle String data in flutter_bluetooth_serial package?

1 Answers1